Method and apparatus for making tubular rivets and the like



R. J. FRETER Aug. 14, 1934.

METHOD AND APPARATUS FOR MAKING TUBULAR RIVETS AND THE LIKE Filed May 12, 1953 5 Sheets-Sheet l K) INVENTOR A TTORNEYS Aug. 14, 1934. R J FRETER 1,970,085

METHOD AND APPARATUS FOR MAKING TUBULAR- RIVETS AND THE LIKE Filed May 12, 1953 s Shets-Sheet 2 0 INVENTOR w Q mmm ATTORNEY- 5 Sheets-Sheet 3 R. J. FRETER Filed May 12. 1935 METHOD AND APPARATUS FOR MAKING TUBULAR RIVETS AND THE LIKE W. wmm

Aug. 14, 1934.

Aug. 14, 1934. R J FRETER 1,970,085

METHOD AND APPARATUS FOR MAKING TUBULAR RIVETS AND THE LIKE Filed May 12, 1953 Sheets-Sheet 4 y '7 I T Q56 &9 r 442 1:: k 'i Z3 4Q 79:

6'9 79- T 41 J l 'Ti 1 INVENTOR BY f R l I wo ATTORNEY Aug. 14, 1934. F;, J, F E 'ER 1,970,085

METHOD AND APPARATUS FOR MAKING TUBULAR RIVETS ANDTHE LIKE Filed my 12. 1953 5 Sheets-Sheet 5 BY 7r effg.

Q Y LM A TTORNEYS Patented Aug. 14, 1934 UNITED STATES PATENT ori ice,

METHOD AND APPARATUS FOR MAKING TUBULAR RIVETS AND THE LIKE Application May 12, 1933, Serial No. 670,767-

26 Claims.

- The present invention relates to an improved method and mechanism for manufacturing tubular rivets, buttons and similar hollowor recessed metallic forms, by displacement or extrusion of the metallic stock, as distinguished from prior methods involving an actual removal of a portion of the structure by drilling or like operations, and for forming such rivet with an enlarged, generally flattened head.

A principal object of the invention is to provide a practicable and eificient method and apparatus, materially simplifying and facilitating the manufacture of articles of this type and for overcoming difficulties heretofore encountered of sticking wherein the metallic stock freezes or sticks to the forming tooldue to the rapidity at which the rivets are formed, without however in any way sacrificing speed of production.

More particularly this invention relates to a combination swaging and heading machine, utilizing a swager driven punch and a crankdriven compression die.

To the attainment of the above, and other objects, which will appear as the description proceeds,-reference may be made to the accompanying drawings in which:-

Fig. 1 is a top plan view of the machine;

Fig. 2 is a side elevation thereof partly in section;-

Fig. 3 is an enlarged sectional elevation illustrating the relation of the swaging and heading mechanism to the work and forming die at the beginning of operations;

Figs ,4 to 7 inclusive are enlarged fragmen tary sectional views similar to Fig. ,3, and illustrating various steps in the manufacture of the article;

- Fig. 8 is a face view of the swaging head looking in the direction of the arrows in 3;

Fig, 9 illustrates a modification of the cam mechanism for the swaging punch;

Fig. 101s a fragmentary view of a slightly different modification of cam mechanism for the swaging punch.

5' Generally speaking, the present machine contemplates feeding a wire of suitable material from a coil to a cutting mechanism which severs a slug or blank therefrom and carries same into operating position in the machine adjacent 'a swaging punch. A crank driven. sliding gate or carriage moves toward the blank, this carriage having mounted therein a die. which receives the blank.

Further movement of the carriage brings an extruding pin from the rear of the die into engagebeing thereby pushed tightly against the swaging punch. The extruding pin is given a constantly forward movement, which is resisted by the slug and swaging punch, the punch being rapidly vibrated or reciprocated longitudinally against the slug, during the entire forming operation until such time as the extruding pin has caused a flow of metal in the slug, outwardly between the swaging punch and die, and also longitudinally of the bore of the die around the penetrating end of the tool, sufiiciently to form a substantially fiat head and a hollow stem thereon, after which the parts return to their original position, and the formed rivet is stripped from the extruding pin and die, dropping into a suitable container.

The series of rapid impingements of the swaging punch against the blank not only materially facilitates the displacement operation by causing an incremental flow of the metal, but also relieves a part of the heavy strain to which the extruding tool is subjected, and avoids the development of excessive temperatures which would tend jointly to. cause rapid deterioration of the tool. This longitudinal vibration also prevents adhesion of the displaced metal to the tool and simplifies the subsequent stripping operation in which the rivet is separated from the extruding pin.

Referring more specifically to the drawings, in which like reference numerals designate like parts, and particularly to Figs. 1 and 2, there will be found the general organization of a frame or base 11 supported by legs 12 and carrying a swaging head 13. Mounted for sliding movement on the frame is a carriage or gate indicated generally at 14. Mounted in bearings 15 is a shaft 16 driven by a fly wheel 17, from any suitable source of power. I

The shaft 16 is provided with an eccentric por-- tion or crank, intermediate its ends at 19, a connecting rod 20 being connected thereto, and also connected to a wrist pin 21 in the gate 14, whereby rotation of the shaft 16 will cause a reciprocation of the gate in tracks or guideways 22. A cutting mechanism indicated generally at 23 completes the general organization, this cutting mechanism including a counterbalance 24 on the shaft 16 having a crank 25 connected to a rod 26, which rod in turn is pivoted at2'7 to a cam slide 28 having a cam track 29 engageable with a cam roll 30 mounted on a transverse bar 31 carrying a cutting mechanism at the end thereof remote from the cam roll.

Swaging head The details of the swaging head can best be pair of wire feed rolls -36 which act to draw the wire from any suitable source of supply (not shown) and feed same into a guide tube 37, the

mouth of such tube being shown at 38 (Fig. 8).

At the point 38 a slug will be cut from the wire and fed to a position in front of the swaging punch 39 by the cutting and feeding mechanism in a manner hereinafter described.'

Extending through the head is a shaft 40 carrying at its outer end a sheave 41 which is power driven by belts 41a at a high rate of speed. Keyed to the inner end of the shaft 40 is a cam 42 which is formed with a number of fiat surfaces 43 respectively separated by slightly rounded points or abutments 44. A bearing sleeve 45 detachably '49, said-splines h'owever; being effectiveto pre- 1 vent relative rotary movement between the punch and the head. The punch is positioned to abut the plunger 46, and the clearance in the keyway 50 is approximately equal to the height of the abutments 44 on the cam 42. whereby movement of the cam will act to force the swaging punch out to its extreme limit. Return movement is effected by pressure of the work against the punch.

As will be evident from the drawings, all parts of the head are detachable and relatively adjustable, and access may be had to any desired part with a minimum of labor.

Cutting mechanism Fig. 1 best illustrates the cutting mechanism, which includes a drive from the counterbalance 24 for the cam slide 29; which, by inter-engagement with the roll 30 tends to produce a reciprocating movement of the .bar 31, there being one complete reciprocation for each rotation of the counterbalance.

Carried by the free end of the bar 31 is a cutting knife or shear 54-and in spaced relation thereto a wire .stop 55, both of which are adjustably carried in the frame 11, adjacent the swaging head 13.

The operation of this mechanism will be readily apparent. Wire is fed through the opening 38 of the tube 37 until it engages the stop 55; the cutter moving transversely of the machine under the influence of the cam mechanism 29-30, past the point 38 causing a slug or work piece W to be sheared from the length of wire, and carrying same to a position in front of the swaging punch 39.

Compression die and heading mechanism adjusting mechanism comprising an adjustable cam or wedge 65 having a set screw 66 effective to adjustably determine the setting of the wedge 65. A wedge block or cam 6'7 is carried by the portion 64 and may be adjustably positioned in the portion 64 by means of an adjusting mechanism 68. r

Interposed between the two sleeves 62 and 63 is a flexible coupling consisting, of relatively stiff springs 69, whereby the sleeve 62 is yieldingly movable in a direction axially of the machine within the sleeve 63. Thus it will be observed that the die 61, the sleeves 6263 and the portion 64 are movable under the influence of the crank drive and portion 14, the wedge adjustment affording means of varying the effective length of the gate thereby in effect varying the effective stroke of the mechanism.

Slidable within the die 61 is an extruding pin '70 carried by a plunger '71. A second plunger '72 is axially aligned with the plunger '71 but spaced therefrom being mounted for movement in a sleeve '73 carried by the portion 64,.-said plunger being aligned for engagement with the wedge block 6'7.

Fixedly carried in 63 is a slide '74 with an abutment '75 thereon. Slide '74 has a yoke end for operating the plunger '71. The slide may be adjusted from the side of the machine as illustrated in Fig. l, by the diagrammatic showing in dotted lines of a bell crank and lever.

Mounted on the base of the machine is an adjustable stop 76 positioned to engage the abutment '75.

Having thus described my invention, the operation thereof will be readily apparent. A length of wire is fed by the rolls 35-36 through the tube 37 until it engages the stop 55 (Fig. 1) and as the crank 19 begins its movement starting the gate to the left of Fig. 1, the rod 26 is starting the cutting mechanism in its transverse movement. A slug W is then cut off by the cutter knife 54 and carried from the cutoff die 'at point 38, over to and directly in line with the heading die and swaging punch (Fig. 3). The heading die 61 in the meantime has advanced under the influence of the main slide or gate to a point almost in engagement with the slug and the end of the extruding pin comes into engagement with the slug, the springs 69 maintaining the telescoped sleeves 6263 in distended relation. By this time the cutter has begun a retrograde movement, and withdraws rapidly to prevent interference with the advancing die, the slug being held between the swaging punch and the extruding pin. The heading die continues its advance movement with the effect that the slug is pushed into the recess of the die as well as' held against the swaging punch (Fig. 4) the pin '70 yielding rearwardly. The continued forward movement of the die to the position shown'in Fig. 4, while the extruding pin is being resisted by 'its engagement with the slug, is permitted by the clearance '78 at the rear of the plunger 71.

Although the cam 42 may be rapidly rotating all this time it will have no appreciable effect on the slug due to the yieldability of the extruding pin rearwardly into the clearance '78. When, however, the heading die reaches the position shown in Fig. 4, the plunger '72 will have reached a position where it is backed up'solidly by the block 6'7 and at this point the swaging punch will start rapidly pounding the slug, as the extruding the slug under the influence of the crank shaft and continued forward movement of the gate.

This operation continues as shown in Figs. 5 and 6, with the swaging punch continuing its vibrating or hammering efiect and the extruding pin being gradually forced into the metal slug W causing the metal of same to flow out in front of the die and also into the punch, mating depressions 79 and 80 being provided for this purpose. It will be quite evident that the metal displaced by the tip of the extruding pin 70 at the inner end of the work will flow longitudinally of the bore of the die, and around the penetrating tip of the tool. The continued movement of the extruding pin after the heading die has reached its outermost limit, i. e., point of engagement with the swaging punch, is permitted by the flexible coupling 69 and the clearance spaces 81 and 82. Fig. 6 shows the operation completed with the crank about to pass its dead center and'at this stage the springs 69 are compressed and the clearance spaces 81 and 82 have been reduced to a minimum and all parts have substantially reached a solid position. 4

As soon as the crank 19 and rod 20 pass dead center the parts return to their original position with a rapid movement as the springs 69 distend the sleeves 62-63, while the crank is retracting the gate. This is shownin Fig. 7 wherein the machine has reached its back or starting position and the completed rivet or work W is ejected. This ejection is efiected by the slide coming into contact with the stationary bumper or stop 76 with the result that the yoke 74 prevents further retrograde movement of the extruding pin 70, although the heading die 61 is still being withdrawn. As the die leaves the swaging punch the efiect of the swaging action of the punch is immediately lost, in fact stops completely as the abutments 44 on the cam will keep the plunger 46 and punch 39, in a forward position. After the die moves away from the punch 39 the slight clearance at 50 permits the plunger to remain forward and free of the cam 42 thus reducing wear on the parts, as the plunger 46 and the punch 39 will be maintained in contact for a very short portion of the cycle of the cam 42. This action of swaging is effective only during the time that the die, the punch and the extruding pin are solidly engaged.

If necessary the work may be automatically stripped from the extruding pin by any suitable stripping mechanism, but ordinarily the vibration of the punch maintains a sufl'iciently free relation between the pin and work, and the relative movement rearwardly between the pin and die will be sufficient to release the work.

In Figs; 9 and 10 are illustrated two modifications of the cam 42, which may be found desirable. In Fig. 9 the equivalent of projections 44 are formed by the use of roller bearings 86 carried by a cage 87, the remaining structure being the same as heretofore described. In Fig. 10 the cam 42 with the projections 44 is unchanged but the end of the plunger 46 is provided with an anti-friction roller bearing 88 projecting slightly beyond the normal end of the plunger 46 to engage with the fproj ections 44.

Having'thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States, is:' Y

1. The method of forming tubular structures which comprises confining a blank in a die in engagement with a pair of working tools, one of which is adapted to extrude the material of the blank within the die, and forcibly relatively feeding said one of said tools and blank together, si-

multaneously with a rapid relative reciprocation between said blank and the other of said tools, thereby to eifect a displacement of the material of the blank by molecular flow around said first tool.

2. The method of forming tubular structures which comprises confining a blank in a die in engagement with a pair of working tools, and forcibly relatively feeding one of said tools and blank together, simultaneously with a rapid reciprocation of the other of said tools, in swaging relation to said blank, thereby to efiect a displacement of the material of the blank by molecular flow around said first tool, within the die, and by molecular flow between the die and said other tool.

3. The method of forming tubular structures which comprises confining" a blank in a die in engagement with a pair of working tools, one of which is adapted to extrude the material of the blank within the die, and forcibly relatively feeding said one of said tools and blank together while resisting unitary movement thereof by the other of said tools, simultaneously with a rapid relative reciprocation between said blank and the latter of said tools, thereby to efiect a displacement of the material of the blank by molecular flow around said first tool.

4. The method 'of forming tubular structures which comprises confining a blank in a die in engagement with a pair of working tools, one

of which is adapted to extrude the material of the blank within the die, and forcibly relatively feeding said one of said tools and blank together thereby to efi'ect a displacement of the material of the blank by molecular flow around the tool, and simultaneously resisting unitary movement of said tool and blank by rapidly impinging the other of said tools against the blank.

5. The method of forming tubular structures which comprises confining a blank in a die in engagement with a pair of working tools, one of which is adapted to extrude thematerial of the blank within the die, and forcibly relatively feeding said one of said tools and blank together simultaneously with a rapid reciprocation of the other of said tools in the line of travel of said blank and first tool while maintaining an engagement between said blank and second tool, thereby to efiect a displacement of the metal of the blank by molecular fiow around said first tool.

6.. The method of forming tubular structures which comprises confining a blank in a die, in engagement with a working tool which is adapted to extrude the material of the blank within the die, advancing the tool in engagement with the blank, and simultaneously resisting such advancement by rapidly impinging another tool against the blank in a direction opposed to the movement of the first tool, thereby to eflfect a displacement of the material of the blank by molecular fiow around the first tool.

'7. The method of forming tubular structures which comprises confining a blank in a die in engagement with a Working tool, advancing the tool in engagement with the blank, and simultaneously resisting such advancement and swaging the blank by rapidly impinging a swaging tool against the blank in a direction opposed to the movement of the first tool, thereby to eiTect a displacement of the material of the blank by molecular fiow around the first tool, and between the die and the swaging tool.

8. The method of forming a tubular rivet which comprises inserting the blank shank of said rivet in a cylindrical die opening, inserting in said die opening, in engagement with the end 'of said shank, a tool of lesser cross sectional area than the die opening, engaging the other end of said blank with a swaging tool, and forcibly relatively feeding said first tool and shank together while simultaneously resisting unitary movement of said first tool and blank by rapidly impinging the swaging tool against the blank thereby to efiect a displacement of the metal of said shank by a progressive incremental flow into and to fill the annular space between the die opening and the path of said first tool.

9. The method of forming a tubular rivet which comprises inserting the blank shank of said rivet in a cylindrical die opening, inserting in said die opening, in en agement with the end of said shank, a tool of lesser cross sectional area than the die opening, engaging the other end of said blank with a swaging tool; and forcibly relatively feeding said first tool and shank together, thereby to erect a displacement of the metal of said shank by a progressive incremental fiow into and to fill the annular space between the die opening and the path of said first tool, while simultaneously impinging the swaging tool rapidly against the blank to resist unitary movement of. said first tool and blank and shape the outer end-of the blank as the material thereof is displaced by molecular flow adjacent the swaging tool.-

10. The method of forming a tubular rivet which comprises inserting a cylindrical blank in a die with one end projecting, simultaneously engaging the outerprojecting end and the inner end of saidblank with a swaging tool, and an extruding tool respectively, and feeding said tools toward each other simultaneously with a rapid reciprocation of the swaging tool, to simultaneously head the rivet and to efiect a displacement of the material of the inner end of said blank by molecular fiow around said extruding tool.

11. The method of forming tubular structures which comprises confining a blank in a die in engagement with a working tool which is adapted to extrude the material of the blank within the die, forcibly relatively feeding said tool and the confined body together. and simultaneously impinging a second tool with a rapid reciprocating movement against the blank in a direction opposed to movement thereof, thereby to effect a displacement of the metal by a progressive incremental fiow into and to fill the annular space between the die wall and the path of said first tool.

12. The method of forming tubular structures which comprises confining a blank in a die in engagement with a working tool which is adapted to extrude the material of the blank within the die, advancing the tool in engagement with the confined blank, and simultaneously resisting such advancement by rapidly impinging another tool against theblank in a direction oppwed to the movement of the first tool, thereby to effect a displacement of the material of the blank by a progressive incremental flow into and to fill the annular space between the die wall and the path of the tool.

13. The swaging method of extruding a metallic body within a sliding die which comprises forcibly relatively feeding an extruding tool and a I swaging punch together in engagement with a metallic body within the sliding die, to effect a displacement of said body by progressive flow into the spaces between the die wall, the extruding tool and punch. and simultaneously with said feed impinging the swaging punch rapidly against the metallic body.

14. The combination with a die having an opening adapted for reception of a metallic body, of a tool adapted for insertion in said opening to engage an end of said body, and a tool arranged to engage the other end of said body, means for relatively feeding said body and first tool, and means for simultaneously rapidly reciprocating said second tool into impinging relation with said body, whereby said tools are conjointly effective to displace the metal of the body by molecular flow around the first tool.

15. The combination with a die having an opening adapted for reception of a metallic body, of a tool adapted for insertion in said opening, to engage an end of said body and a tool arranged to. engage the other end of said body, means for feeding said first tool toward the body, and means for simultaneously rapidly reciprocating said second tool into impinging relation with said body whereby said tools are conjointly operative to effeet a predetermined displacement of the metal of said body within the die.

16. The combination with a die having a cylindrical passage adapted for reception of a correspondingly formed blank, of means positioned- With respect to the die for confining the blank to said passage at one end of the latter, a tool adapted for insertion into the passage to engage the inner end of said blank, means for relatively feeding said blank and tool together, and means for rapidly reciprocating said confining means during thefeeding operation to cause, conjointly with said tool, the material of the blank to have a progressive incremental flow into and to' fill the annular space between the said cylindrical passage and the path of the tool.

17. The combination with a die having a cylindrical passage therethrough adapted for reception of a correspondingly formed blank, of means for closing one end of said passage to confine the said blank, a tool adapted for insertion in the opposite end of said passage into engagement with said blank, said tool having a working tip of lesser cross sectional size than the said passage,

and meansfor relatively feeding said blank and ing adapted for reception of a metallic body, of -a tool adapted for insertion in said opening, and

having a working tip of lesser cross sectional area than said opening, means for forcibly advancing said tool against said body, while the latter is confined in the opening, and means for effecting a series of rapid impingements against the end of the blank opposite said tool during the feeding operation to cause the metal of the body to have a progressive incremental flow into and to fill the annular space between the die opening and the a path of the tip of the tool.

19. The combination with a die having a cylindrical passage therethrough adapted for reception of a correspondingly formed metallic blank. of a swaging tool for engagement with a projecting end of said blank, an extruding tool arranged for insertion in said die passage to engage the inner end of said blank, means for simultaneously feeding the extruding tool against one end of the blank and rapidly impinging the swaging tool against the other end of the blank, thereby to cause the ,metal of the blank to have a progressive incremental flow into and to fill the annular space between the said cylindrical passage and the path of the extruding tool.

20. A combination swaging and heading machine comprising a base, a swaging head thereon having a swaging punch freely movable therein, cam means to actuate said punch, a sliding gate, a heading die carried thereby and positioned for movement along the line of travel of said punch, an extruding tool mounted on said gate for movement therewith and for movement within and relative to said die, crank means to actuate said gate, and means to feed a blank to said die andto locate the blank between said punch and tool.

'21. A combination swaging and heading machine comprising a base, aswaging head thereon having a swaging punch freely movable therein, cam means to actuate said punch, a sliding gate, a heading die carried thereby and positioned for movement along the line of travel of said punch, an extruding tool mounted on said gate for movement therewith and for movement within and relative to said die, crank means to actuate said gate, means to feed a continuous length of wire to said swaging head, means to shear a blank from said wire and feed same to said die in a location between said punch and extruding tool.

22. A combination swaging and heading machine comprising a base, a swaging head thereon having a swaging punch freely movable therein, cam means to actuate said punch, a sliding gate, a heading die carried thereby and positioned for movement along the line of travel of said punch, and for relative movement with respect to said gate, said gate having a fixed member flexibly coupled to said die movable with said gate relative to the die through one portion of the cycle of operations, and effective to positively actuate said die during another portion of the cycle of operations, an extruding tool mounted on said gatefor movement therewith and for movement within and relative to said die, and means to actuate said extruding tool, crank means to actuate said gate, and means to feed a blank to said die for operations thereon.

23. A combination swaging and heading machine comprising a base, a swaging head thereon having a swaging punch freely movable therein, cam means to actuate said punch, a sliding gate, a heading die carried thereby and positioned for movement along the line of travel of said punch, and for relative movement with respect to said gate, said gate having a fixed member flexibly coupled to said die movable with said gate relative to the die through one portion of the cycle of operations, and efiective to positively actuate said die during another portion of the cycle of operations, an extruding tool mounted on said gate for movement therewith and for movement within and relative to said die, means to actuate said extruding'tool, crank means to actuate said gate, and means to adjust the relative positions of the die and extruding tool longitudicam.

nally of said gate, thereby to vary the effective throw of said crank means, and means to feed a blank to said die for operations thereon.

24. In a machine for forming tubular, headed structures, the combination of a die for the reception of a work piece, an extruding tool movable into said die to engage the work piece, means to move said tool, and means engageable with said work piece at the opposite side thereof from said tool, for resisting movement of the work piece under the influence of said tool and for simultaneously forming a head on said work piece comprising a swaging head having a rotatable shaft therein, a cam carried by said shaft, said cam having a plurality of protuberances peripherally spaced therearound, a swaging punch carried by said head and having one end positioned adjacent said cam protuberances, said punch being splined for re-- ciprocable movement a distance equal to the height of said protuberances, whereby rotation of said cam will effect a series of impingements against said punch, and means to resist movement of the punch away from the cam.

25. In a machine for forming tubular, headed 1 structures, the combination of a die for the reception of a work piece, an extruding tool movable into said die to engage the work piece, means to move said tool, and means engageable with said work piece at the opposite side thereof from said tool, for resisting movement of the work piece under the influence of said tool and for simultaneously forming a head on said work piece comprising a swaging head having a rotatable shaft therein, a cam carried by said shaft, said N cam comprising a cage and a series of anti-friction bearings peripherally carried thereby with outer surfaces projecting beyond the periphery of the cage, a swaging punch carried by said head and having one end positioned adjacent said anti-friction bearings, said punch being splined for reciprocable movement a distance equal to the height of said projecting surfaces, whereby rotation of said cam will effect a series of impingements against said punch, and means to resist movement of the punch away from the 26. In a machine for forming tubular, headed structures, the combination of a die for the reception of a work piece, an extruding tool movable into said die to engage the work piece, means to move said tool, and means engageable with said work piece at the opposite side thereof from said tool, for resisting movement of the work piece under the influence of said tool and for simultaneously forming a head on said work piece comprising a swaging head having a rotatable shaft therein, a cam carried by said shaft, said cam having a plurality of protuberances peripherally spaced therearound, a swaging punch carried by said head and having one endpositioned adjacent said cam protuberances, and an anti-friction bearing interposed between said cam and said punch, said punch being splined for reciprocable movement a distance equal to the height of said 140 protuberances whereby rotation'of said cam willefiect a series of impingements against said punch, and means to resist movement of the punch away from the cam.

ROY J. FRE'I'ER. 

